paeds948
A 4-year-old boy is brought to your clinic by a worried mother who complains that he’s still unable to walk. On observing the child on the ground in a supine position, you notice the following events:First, the child rolled into prone, extended his arms and legs far apart. With the trunk weight resting on the extended arms, he pushed the body backward to shift the weight of the trunk over the extended legs.Realizing what you just observed, which among the following is the most important test you would recommend?